This part of ISO 4759 establishes a selection of tolerances for use in the preparation of ISO product standards for punched plain washers of product grades A and C, for use with bolts, screws and nuts of nominal thread diameters of from 1 mm to 150 mm inclusive.It is recommended that these tolerances also be used for non-standard washers.NOTE The product grade refers to the quality of the product and to the size of the tolerances.Annex A (informative) presents tolerances taken from ISO 286-1 and ISO 286-2.